Hydraulically operated combined threading and turning machine



May 4, 1943. s. w. MATHIAS 2,318,177

HYDRAULICALLY OPERATED COMBINED THREADING. v

- AND TURNING MACHINE Filed Aug. 3, 1940 3 Sheets-Sheet 1 INVENTOR.Sqmae! h Mal/aims ATTORNEY6 May 4, 1943.

HYDRAULICALLY OPERATED COMBINED THREADING AND TURNING" MACHINE I FiledAug. 3, 1940 3 Sheets-Sheet 2 (S'amzm/ W. Mathias 5 w. MA'rHIAs 2318517?v May 4, 1943.

S. W. MATHIAS HYDRAULICALLY OPERATED COMBINED THREADING AND TURNINGMACHINE Filed Aug. 3. 1940 5 Sheets-Sheet 3 INVENTOR.

Samuel W Mathias BY WW ATTORNEYS Patented May 4, 1943 THREADING ANDTURNING MACHINE Samuel W.'Mathias, Waynesboro, Pa., assignor' to LandisMachine Company, Waynesboro, Pa., a corporation oi PennsylvaniaApplication August 3,

19 Claims.

This invention relates to a combined threading and turning machine, moreespecially to a machine of this type which is hydraulically operated.

While both hydraulically operated threading machines and hydraulicallyoperated turning mechines have been known for many years, it hasheretofore been considered impractical to devise a combined machinewhose hydraulically actuated mechanisms could selectively be combinedand utilized to perform their required functions equally well regardlessof whether the machine was to be employed for threading or for turning,and insuch manner as to have the performance thereof equal or superiorto machines specifically designed for but one type of operation.

The inherent nature of hydraulically operated machines specificallyadapted for turning gen erally has made them entirely unsuitable forthreading operations, for such machines do not incorporate theexceedingly precise synchronism of relative axial and rotative movementbetween the cutting tool and the work required for threading operations.Neitherare they capable of effecting the appreciably lower cutting feedscommon to threading. Occasionally, a limited character of rather crudethreading operations is performed on these machines, in which casechanges of a makeshift character are made in the turning machines.

Likewise, the inherent nature of hydraulically operated threadingmachines generally has precluded their use for commercial turningoperations, for the characteristics which specifically adapt them forthreading largely are obtained at a sacrifice of the productivitynormallyexpected of a machine which primarily is designed for turning.

My improved machine in its threading condition is capable of being usedto effect an initial leadscrew motion between the work and the threadingelements and subsequently to permit the latter to serve as their ownleadscrew mechanism.

When the nature of the engagement between the work and the cuttingelements or the nature of the axial cutting thrust forces precludehaving the cutting elements function in such manner, as when veryshallow or very coarse threads, respectively, are to be cut, the machinemay be operated to effect a leadscrew motion during the entire threadingoperation. Furthermore, threads of widely varying forms, pitches, leads,lengths. and diameters maybe cut with relatively equal ease. Stillfurther, the machine may be modified 1940, Serial No. 351,012

toproduce either external or internal, tapered, or straight threads. I

In its turning condition, the improved machine is capable'of eithercoarse or fine axial turning 5 feeds or both in sequence. Further; itmay be.

used to both turn and face thework which can be of widely varyinglengths and .diameters. Still further, my improved machine may bemodified to produce either. externalor internal, straight,

In or tapered turned surfaces.

Other useful operations that may be performed therewith will be apparentto those skilled in the art.

Basically, the invention comprises a work carrying'member, a toolcarrying member, and a member supportingthese two and incorporating aplurality ofcombined hydraulically actuated mechanismsfor effectingvarious types of desired axial movement between the work carrying andthe tool carrying members. Novel hydraulically actuated means areprovided for effecting relative axial work and tool movement, one of theunique features being the fact that the initial rapid forward movementof the carriage to opcrating position may be interrupted and themovement of the carriage slowed or retardedto provide a work chuckingperiod, during which period certain types of work may be centered onboth the work carrying and tool carrying ma- 80 chine members. Aftersuch chucking has been effected, the rapid forward movement of thecarriage may be resumed so as to minimize the non-cutting portion 'ofthe the duration of this delayed be controlled at will by the entirecycle. Since operator, and since its timing within the rapid workpositioning portion of the cycle can be established to suit Wide- 1yvarying lengths of work, the useful scope of this feature is greatlyenhanced.

closure cpmprisesa tool carrying member which is rotatably mounted onthe machine frame and which may be of the. type disclosed in UnitedStates Patent 1,760,568, utilizing tool assemblies of the general typedisclosed in United States Patent 1,738,847. The work carrying member-isslidably mounted on the machine frame and is essentially similar to thatdisclosed in my copending application Serial No. 199,527, filed April 1,1938, which has matured into PatentNo.

2.215.270, of Sept. 17, 1940. As such, the machine would best be adaptedfor the external threading of straight threads; or by substituting plaincutters for the thread-cutting elements and effecting 5 minoradjustments of the operation of the hychucking period-can In a preferredembodiment, the present disdraulically actuated mechanisms, it wouldequally well be adapted for the turning of cylindrical surfaces.Further, both tapered threads and conical surfaces may, respectively, bethreaded or turned thereby, providing that suitably tapered cuttingelements of the correct cutting configuration are employed and that thelength of threaded or turned surface does not exceed the permissiblelength of engagement between the cutters and the work.

In a further embodiment of the invention, external cutting tools, of thetype disclosed in United States application Serial No. 268,966, filedApril 20, 1939, which has matured into Patent" No. 2,291,919, of Aug. 4,1942, or the rotary pullofl type tool disclosed in United States Patent2,154,006, may be rotatably mounted on the machine to cut externalthreads and for turning purposes. Further, should it be desired toproduce externally threaded or turned surfaces having a generated taper,a mechanism of the type disclosed in copending application Serial No.350,811, filed on even date herewith, which has matured into Patent No.2,291 ,758, of Aug. 4, 1942, may be employed.

My improved machine mayalso be arranged for internal straight threadingand turning by utilizing'a rotary type tool of the character disclosedin copending application Serial No. 327,731, filed April 4, 1940, whichhas matured into Patent No. 2,283,280, of May 19, 1942. Further, bothtapered internal threads and tapered bores may be produced therewith byusing suitably tapered cutting elements of the correct cuttingconfiguration when the length of threaded or bored surface does notexceed the permissible length of engagement'between the cutters and thework. Likewise, a fully generated internal tapered thread or bore may beproduced by utilizing a tool of the character disclosed in United StatesPatent 2,054,029,

In further embodiments of the invention, the work may be rotatablymounted on the carriage member, while cutting tools'of the types shownin the aforementioned patentsand applications may be mounted on themachine frame. These sametools may be rotatably mounted on the carriagemember, while the work may be held by a yoke operated chuck carried bythe machine frame. These same tools may also be mounted on the carriagemember, while the work may be held and rotated by a rotatable yokeoperated chuck carried by the machine frame.

It is a primary object of my invention to provide a hydraulicallyoperated combined threading and turning machine which is adaptable for awide variety of turning and threading operations by means of adjustmentsof its normal complement of machine units.

It is another major object of my invention to provide an improvedautomatic combined universal threading and turning machine which isadaptable to a wide variety ofthreading or turning operations.

A further important object is to provide a machine with hydraulicallyactuated means causing an initial rapid-relative axial movement betweenthe work holder and the cutting elements to minimize the time ofnon-productive operation of the machine, which rapid movement mayautomatically be retarded to permit a delayed centering and chucking ofthe work.

ting elements are quickly disengaged from the work at the end of acutting operation.

Further objects will become apparent from the following specificationand the accompanying drawings, and from the appended claims.

In the drawings:

Figure 1 is a front elevation of a preferred embodiment of my invention,the tool carrying member comprising a cutter head which is rotatablymounted in the machine frame and the work carrying member comprising aclamping device which is mounted on an axially slidable carriage that isadapted to undergo various controlled axial movements determined andeffected by a combination of automatically actuated mechanism mounted onthe carriage and the machine frame.

Figure 2 is a schematic diagram of the automatically actuated mechanismsand their conmotions with each other and with the work carrying and thetool carrying members.

Figure 3 is a partial view showing the automatically actuated mechanismsdisposed to effect a typical turning operation.

Figure 4 is a partial view showing the automatically actuated mechanismsdisposed to effect a typical threading operation.

Figure 5 is a partial sectional view showing details of the springpressed center assembly construction.

Referring to Figure 1, the machine comprises a frame i0 which hasmounted therein a motor (not shown) and change speed and reversegearfiled on April 1, 1938.

Mounted on tool spindle II is a cutter head 20, the one shown being ofthe same generaltype as that disclosed by Shearer'in United StatesPatent 1,760,568 and incorporating cutter assemblies 2| of the typefurther disclosed by Shearer in United States Patent 1,738,847, whichassemblies employ cutters 22 whose cutting edges 23 are tangentiallydisposed to the work and may be plain, for turning, or serrated, forproducing a .desired form of thread.

Referring to Figures 1 and 2, cutter head 20 incorporates anoperatingring 25 which is adapted to be actuated by a yoke mechanism 26,pivotally mounted on frame ID, to effect disengagement of cutters 22from the finished work and to effect a resetting of the cutters tooperating position. The manner in which the yoke mechanism and theoperating ring coact for these purposes is well known to those skilledin the art and is fully described in United States Patent -draulic motor21 is connected by piston rod 28 to the yoke mechanism 26. The resettingmovement of the yoke mechanism is adapted to be effected by a mechanicallinkage-30, pivoted to the frame at 29 and-connected to theyoke. A rod3! connected to the linkage has thereon adjustable abutments 32 that arecontacted by carriage l6 to actuate rod 3| and linkage 30, rod 3| beingslidable in the carriage.

Referring more particularly to Figures 1 and 5, cutter head 28 furtherincorporates a central bore 35 in which is mounted a non-rotatablesleeve 35 carried by a rearwardly extending housing 31 which forms partof frame l0. Axially movably keyed within sleeve 36 is a center 38having an enlarged annular portion 39 adapted to contact the end surfaceof a ring 48 threaded into'the forward end of sleeve 36, being pressedthereagainst by a. spring 4| located within sleeve 36 and abutting therear portion ofcenter 38.

Sleeve 36 may be longitudinally adjusted, with respect to the housing31, by rotating it with respect to the means 42 which has a force fit inthe end of housing 31 and an internal thread engaging a cooperatingthread on the end of sleeve 36. A collar .44 is pinned to sleeve 38 andprovides means for turning thesleeve within the means 42. A locking nut43 is also threaded on means 42 and serves to lock sleeve 36 inadjusted'position by frictional engagement with the collar '44 which ispinned to the sleeve. The center may thereby be positioned more or lessforward of cutter assemblies 2| to facilitate the centering.

of different types of work.

A hydraulic motor 45 is utilized to effect axialmovements of carriageI6, having a piston rod 46 which is connected to a dependinglug 41 ofthe carriage. Adjustably mounted on rod 46 is a collar 48 adapted tocontact a fixed abutment 49 of frame ID to limit the axial movement ofcarriage |6 toward cutter head 20.

A main control valve 58 is mounted on frame l and has a plunger mountedtherein to be disposed in anyof a plurality of controlpositions. A foottreadle 53 is mounted on 'frame l0 tudinal T-slot 56 adapted to receivea plurality ofdogs 51, 58, 59 and 60, which are adjustably clampedtherein and removable therefrom and which during the operation of themachine coact with a roller 6| carried by plunger 5| to depress or raisethe plunger to different control positions.

Main control valve 58 has associated therewith a valve 65 fordetermining the rate of coarse axial work-feed and a second valve 66 fordetermining the rate of fine axial work feed. Both of these valves areadjustable, being set by the machin operator.

A dog is adjustably positioned in T-slot 56V to coact with springpressed plunger 1| of a valve 12. This valve serves as a means forinterrupting the normal rapid initial movement of carriage l6 towardcutter head 20, whereupon the carriage' proceeds with a retardedmovement to permit centering the work on the center 38. As will bedescribed later, a manually adjustable valve is utilized to determinethe speed of the retarded carriage movement.

T-slot 56 further is provided with a dog 16 which is adapted to actuatea quick-act ng valve 11 that serves as a hydraulic trip for actuatinghydraulic motor 21 to effect a cutter disengaging operation of yokemechanism 28. To effect quick actuation of valve 11, dog 18 is adapted,during the motionof carriage 6, to engage an abutment 8| on rocker .18.The rocker is rockably mounted onthe frame l0 at the pivot 84 and isslidably engagedbetweenshoulde'rs 81' and 88 on the valve stem 19. Thelower end of rocker '18 carries a roller which cams with a conicallypointed detent 82 s'lidably mounted in frame l0 directly below pivot 84:and having a spring 83 therein to maintain it in camming contact'wlth 1the roller 88. Thus, as dog,16 in its motion engages and rotates rocker18 in a clockwise direc- 1- tion, roller 80 thereof depresses detent 82against the action of spring 83. As roller 18 rides across" the top ofthe cone point of detent 82, spring 83 serves to effect a rapid cammingtherebetween to cause rocker 18 to have a snap action clockwise"movement.

shoulders 81 and 88 the snap action of the rocker will move the'ValVestem .19 to the left with a similar snap action. There is, a-certainamount of lost motion betweenthe shoulders 81-88 and the rocker so thatthe valvestem will not be moved While the rocker 18 is moving slowly anddepressing the detent 82 before the snap action occurs.

When it is desired to face a shoulder on turned work, valve 11 isfurther adapted to be connected to a valve 85 that is manuallyadjustable to delay the operation of the hydraulic motor .21, wherebycutters 22 can engagea face of the work to finish the same before theydisengage therefromandwhereby tool marks, such as those commonly formedat the end of a cut, may be removed from the turned surfaces of thework. A manually operated cut-out valve 86 is provided for connectinganddisconnecting valve 85 from valve 11.

As hydraulic motor 21 effects cutter disengaging motion ofyoke'mechanisrn 26-, it also actuates linkage 38 to have member 98thereof contact a rod 9| to depress a plunger 92 of afvalve83 whichvalve, by means of'hydraulic connections to be later described, servesto move plunger 5| of the main control valve 58 to carriage returnposition.

A pump 95 is provided to draw exhaust fluid from a return tank 96 tointroduce it back into the circuit as high pressure fluid. A by-p assrelief valve 91 discharges fluid back into the tank 98 if the pressureon the discharge side of the pump becomes too great.

Other auxiliary mechanisms, connections/and valves are incorporated inthe circuit, and these will be described during the description. of theoperating cycles of the machine.

Turning operation Referring now to'Figure 3, the'dogs 10, 58, 59, and 16are disposed in T-slot 56 of carriage I6 to control a typical turningoperation. This operation includes centering the work, making a coarseand a subsequent fine turning cut, and facing a work shoulder when therelative axial movement between the work and cutters 22 has been stoppedby the engagement'of collar 48 with the frame abutment 4 9. Cut-outvalve88 will be openas shown in Figure 2, to permit-of carriage delay. forshoulder facing, and valves 15, 65, 66, and 85.

will have been adjusted to regulate, respectively, the chucking feed,the coarse axial feed, the fine axial feed, and the facing time period.

Rapid carriage advance 7 Referring to both Figures 2 and 3, when theSince the rocker is engaged between operator depresses the foot treadle53, plunger 5| of control valve 50 is moved upwardly to cycle startingposition. Pump 95 draws fluid from tank 96 through line I and directshigh pressure fluid out through line IOI and connecting line I02.By-pass relief valve 91, connected to line IOI, permits any excess fluidto return to tank 96 through line I03.

The high pressure fluid in line I02 flows through connecting lines I04and I05 to check valve I06, whose purpose later will be explained. Thefluid leaves valve I06 and is directed to port I01 of control valve 50by lines I08and I09. At this time port I01 is open to ports H0 and IIIthus the fluid passes'out of these ports through lines II2;and II3,respectively, which connect with.

line II 4 that directs the fluid to port II5 of hydraulic motor 45 toeffect rapid movement of piston rod 46 to the right,- whereby carriageI6 is rapidly pulled toward cutter head 20.

Piston rod 46 is permitted to move rapidly to the right, since theexhaust from motor 45 can flow freelyback to tank 96, as follows.Exhaust fluid leaves motor 45 through port H6 and is directed by lineI2I to port II9 of valve I20, Valve I20 contains a plunger I22 which isconstantly urged to the right by spring I23. At this time, plunger I22is in its rightmost position, which permits the exhaust fluid to flowfrom port II9 out through port I24 to line I25. Line I25 directs theexhaust fluid to feeder line I26 from which it flows through line I21 toport I28 of control valve 50. Withcontrol valve 50 still incyclestartingposition, port I28 is open to port I29, the exhaust fluidleaving valve 50 through that port and flowing out through line I30 andconnecting line I3I to tank 96. g

It is to be noted that any fluid entrapped in the upper end of valve 50can exhaust to tank 96 through port I32 and line I33 which connectsvwith line I3I that leads to. tank 96. Thus, the upward movement ofplunger 5I to cycle starting position is not hindered.

Centering and chucking II6 of motor 45. It is to be noted that theinitial rapid advance of carriage I6 brings dog into camming contactwith the upwardly protruding portion of plunger H of valve 12. The spaceabove th e plunger in the valve body is suitably vented to allowmovement of the plunger. As plunger H is depressed, high pressure fluidin line I04 is permitted to flow through line I05 to port I34 by valve12 and out through port I35, plunger II being depressed at this time.The fluid then passes through line I36 which directs it to port I31 ofvalve- I20. The pressure of this fluid against the end of plunger I22 ofvalve I 20 is such as to move the plunger leftwardly against the forceof spring I23. It should be noted that any fluid entrapped in the leftend of valve I20 may flow out through port I41 thereof through line I48and connecting line I46 to tank 96 as plunger I 22 is moved leftwardly.With the plunger I22 now in its leftmost position, exhaust fluid fromport II6 of motor 45 is permitted to flow through line I2I to port II9of valve I20 and out through port I40 thereof to line I4I which directsit to port I42 of valve 15.

Valve has a manually adjustable valve stem I 43 which restricts the flowof exhaust fluid from port I42 to port I44 thereof. The restricted flowof exhaust v fluid is directed from part I44 to line I45 and connectingline I46 which directs it back to tank 96.

It should be noted that the position of dog 10 within 'T-slot 56 of.carriage I6 determines the instantat which such carriage'retardationcommences, Likewise, the setting of valve stem I43 determines the rateof carriage movement during the retarded period. The rate of carriagemovement during the retarded period, together with the length of cammingface I50 of dog 10, establishes the time period for centering andchucking the work, the duration of which period is preferably set byadjustments of valve stem I43, the length of camming face I50 of dog 10preferably being standardized.

Resuming rapid carriage advance Certain types of work are necessarilycentered and chucked while still disposed a considerable distanceforward of the cutter head 20. Consequently, to minimize the timerequired to bring the ,work into engagement with the cutters 22,

the rapid carriage advance is resumed; that is,

12 and to open port I35 to port I55 thereof. Since port I55 is connectedto tank 96 by line I 56 and connecting line I3I, spring I23 in valve I20now can move plunger I22 rightwardly, the fluid in the right-hand end ofvalve I20 exhausting out through port I31 through line I36 to port I35of valve 12, through port I55 thereof and to tank 96 by line I56 andconnecting line I3I.

Thus, port II9 of valve I20 again is open to port I24 thereof, andexhaust fluid from motor 45 flows out to tank 96 as has previously beendescribed in the description of the rapid carriage advance phase of thecycle.

Coarse axial feed As carriage I6 approaches cutter head 20, and justbefore the work is engaged by cutters 22, the continuing rightwardmovement of the carriage causes dog 59 to coact-with roller 6I todepress plunger 5I of main control valve 50 to coarse axial feedposition. In this position of plunger 5|, ports I01 and III still areopen to each other and port I60 now is open to port I6I, the remainingports of valve 50 being blocked.

High pressure fluid continues to flow from port I01 to port III and toport II5 of motor 45 through line H3 and connecting line II4. Like wise,the exhaust from motor 45 continues to flow from port II 6 thereof,through valve I20 f and to feeder line I26, as is described under thedescription relating to the rapid carriage advance phase of the cycle.

Feeder-line I26 now directs the exhaust fluid from motor 45 to line I62which connects with port I60 of valve 50. The exhaust fluid passes toport I6I and out to duct I63 around manuallyregulated coarse feedadjustment valve 65 and dog 59 can be adjustably positioned in T-slot 56of carriage I6 to cause this feed action to start immediately upon orprior to the engagement of cutters 22. with the work.

a Fine axial feed As has been stated previously, the arrangement shownin Figure 3 is employed for a turning cycle which has a coarse axialfeed phase and a subsequent fine axial feed phase. Such subsequent fineaxial feed would be desirablewhen a superior finish would be required onthe end of the work that is nearest to clamping device I8. Or, thecutters 22 may have their cutting edges 23-formed to progressively turna plurality of progressively enlarged work diameters and thelatter ofthese may require a fine finish.

. As the coarse axial feed phase of the turning cycle nears completion,the continued rightward movement of carriage I6 causes dog 58 to depressplunger of main control valve 50 to fine axial feed position. In thisposition of control valve 50, ports I01 and I both are open to port III,and port "I is open to port I12, the remaining ports being blocked.

High pressure fluid flows from line I08 to port III by passing throughline I09 and port I01 and simultaneously through line I13 and port I10;The manner in which this high pressure fluid leaves port I I I toactuate motor 45 and the manher in which exhaust fluid from motor 45returns to feeder line I26 is described in the description relating tothe rapid carriage advance phase of the cycle.

Exhaust fluid is directed from feeder line I26 to port "I by line I14.This fluid passes through port I12 to line I15 and subsequently to ductI16 which directs it around manually-regulated fine axial feedadjustment valve 66 from which it passes, by duct I65 to line I66and'line I,3I into tank 96.

Obviously, valve 66 may be set to effect difierent desired rates of fineaxial feed and dog 58 may be adjusted to have this feed commence at anydesired time after the start of the coarse axial feed phase of thecycle.

Further, should the character of the work, etc., tend to producefluctuations in the rate of volume of exhaust fluid leaving port II6 ofmotor 45, a common type of automatic volume rate stabilizing mechanismI18 (represented schematically in Figure 2) can be associated with valve66 so that the fluid flow thererhrough does not falter; likewise, asimilar mechanism I19 (also represented schematically in Figure 2) canbe associated with valve 65 for the same purpose.

Facing As carriage I6 nears the end of its fine axial feed movements,dog 16 starts to rotate rocker 18 clockwise to cause plunger 19 of valve11 to be moved leftwardly. At the instant when roller 80 of rocker 18experiences the fast camming movement caused by the upward movement ofspring pressed detent 82, collar 48 on piston rod 46 of motor 45contacts frame abutment 49 to stop the rightward movement of carriageI6.

The cutters 22 of cutter head now are wiping the turned surfaces of thework so as to remove any tool marks and can serve to face shoulderslocated on the Work.

passing out through Prior to the leftward movement of plunger 19of'valve 11, high pressure fluid is pressing plunger I to the left-handend of valve I8I against the force of spring I82. This is possiblebecause of the fact that the high pressure fluid in line I05 is open toduct I83 of valve I8I. Note that line I84 connects with line I05 andalso with'line I85 leading to port I86 of valve 11. This port is open toport I81 when valve plunger 19 is in its rightmost position. Line I88leads from port I81 to line I89 that connects with port I90 of cut-outvalve 86. Valve 86 is in open position so that port I90 is open to portI9I' thereof. Line I92 leads from port I9I to duct I93 of valve IN; andduct I93 is connected to duct I83 by duct I94 of valve I6I.

Now, the leftward movement of plunger 19 of valve 11 opens port I81 toport I91 so that the fluid in the right-hand end of valve I 8| can bedisplaced to tank 96 by rightward movement of plunger I 80, as effectedby spring I82. For returning the fluid to'tank 96, port I91 isconnected'by line I98 to line I99 which connects with line I46 thatleads to tank 96. Further, any fluid entrapped'in the left-hand end ofvalve 11 can flow to tank 96 by passing out through port 200 whichconnects with line I99.

Since manually-regulated facing time period adjusting valve 85 isdisposed between duct I83 and duct I 94, the position of this valvedetermines the rate at which the fluid in the right-hand end of valve'I8I can exhaust to tank 96. Consequently, valve 85 determines the totaltime required for plunger I80 to be moved by spring I62 to theright-hand end of valve I8I, which time elapse, as later will beevident, is the time period during which facing of the work can beeifected. Further, since valve 85 is adjustable, the length of facingtime period is adjustably established thereby.

Cutter head opening As spring I82 gradually forces plunger I80 of movedrightwardly. The fluid entrapped in the right-hand end of valve 201 canflow to tank 96 by port 2I0 and line I88 to port I81 of valve11 whoseplunger 19, being in its leftmost position, has opened port I81 to portI91 which is connected to tank 96 by lines I98,

I99 and I46.

With plunger 208 of valve 201 now in its rightmost position, port 2 isopen to port 2I2. High pressure fluid from line I04 nowcan flow fromport 2 through port 2| 2 and line 2I3to piston rod 26 then is forcedleftwardly. Any fluid entrapped in the.

left-hand end of motor 21 flows to tank 96, passing out port 2I5 andline 2I6 to tank 96.

Since leftward movement of piston rod 26 causes yoke mechanism- 26 tomove operating ring 25 rearwardly on cutter head 20, the cutters 22 arecaused to disengage from the finished work. Likewise, since suchleftward movement of piston rod 28 does not-occur until plunger I80 ofline I 46 leading to l hand end or motor 45 is Rapid carriage return Aspiston rod 28 of valve 21 moves leftwardly to actuate yoke mechanism 26,the member 90 of linkage 30 also is actuatedto press rod 9I rightwardly.Rightward movement of rod 9| presses plunger 92 of valve 93 to the rightagainst the force of spring 220. Any fluid entrapped in the right-handend of valve 93 passes out port 22I thereof to line I46 which leads totank 96.

When plunger 92 is in its rightmost position, port 222 is open to port223. High pressure fluid now can flow from line I84 through ports 222and 223 to line 224 which leads to port 225 of hydraulic motor 226 andpiston rod 221 of motor 226 will be moved to the right. Any entrappedfluid in the right-hand end of motor 226 passes out port 228, line 229,line I3I and into tank 96.

Since piston rod 221 has a camming connection 230 with linkage mechanism54, the rightward movement of piston rod 221 causes plunger SI of maincontrol valve 50 to be moved further downwardly.

As plunger 5| moves downwardly, it eventually assumes a position inwhich port H is open to port I32, ports I01 and I10 still are open toport III, and port I28 is open to port I29. This normally is the stopposition. At this time high pressure fluid from line I then can flowthrough valve I06, through line I08, and simultaneously through line I09and port I01 and line I13 and port I to port III and out to line II3,then through line II2 to port IIO, through which it passes to port I32and out to tank 96 by lines I33 and I3I. The pressure in the systembeyond valve I06 drops to a low valve since it flows unrestrictedly intothe tank. The valve I06, however, due to the action of a spring againsta ball seating on the inlet port, 'maintains a sufficiently highpressure in lines I84 and 224 leading to motor 226 to continue to moveplunger 5| of valve 60 further downwardly until it assumes carriagereturn position.

In carriage return position of plunger 5|, port H0 is open to port I32and port I10 is open to port 235, the remaining ports being blocked.Consequently, the pressure in the system again rises, and high pressurefluid flows through valve I06 to line I08 and line I13, which lead toport I10 that is open to port 235. The high pressure fluid then leavesport 235 by line 236, feeder line I26 and line I25 to flow to port I24of valve I20. Since port I24 is open to port II9, the fluid flowstherethrough and through line I2I to port H6 01 motor 45 to start therapid return or carriage I6, which is pushed leftwardly by the pistonrod 46 of motor 45. The entrapped fluid in the leftexhausted to tank 96by passing out port H5 and line II4, to line H2, and to port IIO. Sinceport IIO now isopen to port I32, the exhaust fluid from motor 45continues through port I32, line I33, and line I3I to tank 96. Thisunrestricted flow of the exhaust from motor 45 permits or rapid carriagereturn.

As the carriage I6 starts its return movement, dog 16 engages abutment89 on rocker 18 to impart a counter-clockwise p action rocker 18 due tothe action of spring pressed detent 82. Rocker 18 snaps plunger 19 ofvalve 11 back to left-hand end of valve 201.

its rightmost position in valve 11. The entrapped fluid in the righthandend of valve 11 flows to iiairk 96 through port I91 and lines I98, I99and With plunger 19 again in its rightmost position, port I86 is open toport I81 and port 200 is open to port 203. High pressure fluid flow fromline I84 to line I85 to port I86 and out through port I81 and line I88to port 2) of valve 201 to move plunger 208 back to itsoriginal'position in the The entrapped fluid in the left-hand end ofvalve 201 passes out through port 206, through line 205 to port 202 ofvalve I8I. As will later be evident, it flows on to tank 96.

Simultaneously high pressure fluid from line I88 flows through line I89and ports I90 and I9I of valve 86 to line I92 which connects with ductI93 ofvalve I8I. The fluid passe from duct I93 into duct 240 and throughcheck-valve 24I into duct I83 of valve I8I to again force plunger I toits original position in the left-hand end of valve I8I. Duct 240 andcheck valve 24I are provided so that no delay is experienced in movingplunger I80 leitwardly, as would be the case if the fluid had to enterduct I83 through the restricting valve 85. The check valve 24I furtherprevents flow from duct I83 to duct I93 so that exhaust fluid from valveI8I must pass around valve during the facing time delay periodpreviously described.

The fluid entrapped in the left-hand end of valve I8I flows freely totank 96, this end of the valve having a port 245 that is connected toline 246 which directs the exhaust fluid to line I99, and thereupon toline I46 leading to tank 96.

With plunger I80 of valve I8I again in its leftmost position, theexhaust fluid from the lefthand end of valve 201 flows from port 202 ofvalve I8I to duct 241 and past check valve 248 to port 249 which now isopen to port 20I. This exhaust fluid leaves port 20I by line 204 and isdirected to port 203 of valve 11, thence to port 200, line I99, lineI46, and into tank 96. Check valve 248 prevents any flow of highpressure fluid from port 20I of valve I8I to port 206 of valve 201 byway of port 249 and duct 241 of valve I8I during the facing time phasesof cycle operation. Such flow must be from port 20I to port 202, andoccurs only after plunger I80 of valve I8I has moved to the rightmostposition to connect ports 20I and 202. V

Thus, valves 11, I8I, and 201 again are now in their original positionsfor the start of the next cycle which will begin when foot treadle 53isactuated again.

Cutter head resetting As carriage I6 approaches the end of its returnmovement, depending portion 41 thereof contacts adjustable abutments'32on rod 3| of linkage 30 to actuate yoke mechanism 26 so as to moveoperating ring 25 of cutter head 20 forwardly to cause cutters 22 to bereset to their cutting position for the next cycle.

Since this movementof the yoke mechanism causes piston rod 28 of motor21 to be moved to the right, this motor again i back in its initialposition. Entrapped fluid in the right-hand end of motor 21 can flow outto tank 96 by passing out,through.port 2I4 and line 2I3 to port 2I2 ofvalve 201 and on through port 250 to line I46 leading to tank 96.

The leftward movement of rod 3I of linkage 30 also causes member torotate out of engagement with rod 9| which is holding plunger 92 01'valve 93 in its rightmost position against the force of spring 25I.Spring 25I now moves plunger 92 to the left, whereby the fiow of highpressure fluid from port 222 to port 223 and on to motor 226 is stopped,port 222 again being blocked as it formerly was.

Simultaneously with these above-mentioned operations, camming face 252of dog 60, which dog is carried by T-slot 56 of carriage I6, engagesroller 6| of plunger5| to move it into stop position, which position hasbeen described under the description relating to the carriage returnphase of the cycle. The fluid from pump 95 now is completely by-passedby valves 91 and I06; and, since motor 226 now cannot actuate plunger 5|because the plunger 92 of valve 93 i no longer depressed to permit highpressure fluid to reach motor 226, pump 95 remains in by-passed relationto the remainder of the circuit until the operator again depresses foottreadle 58 to start a new cycle.

Taming cycle variations It is evident that when work not requiringmounting on centers is to be turned, it may be clamped in clampingdevice I9 prior to the start of the turning cycle, and dog I may beremoved from T-slot 56 of carriage I6 to eliminate any centerin andchucking period. Carriage I6 will then go from initial rapid advance tocoarse axial feed motion without experiencing any reduced forward motionas required for centering and chucking.

Likewise, either coarse axial feed motion or fine axial feed motionmay-alone be used for the tuming period. For coarse axial feed, dog 59is retained in T-slot 56 and dog 56 is removed; while for fine axialfeed, dog 58 is retained in T-slot 56 and dog 59 is removed.

Further, certain types of work may require but rough turning and mayhave no shoulders thereon. In such cases, the necessity for eliminatingtool, marks and for facing of shoulders is eliminated, and the timedelay for such operation can be dispensed with to increase theproductivity of the machine.

The facing phase of cycle operation can be eliminated by having plungerin stop position (as is shown in Figure 2) and pulling plunger I9 ofvalve 11 into its leftmost position. This enables the spring I82 ofvalve |8I to move plunger I80 to the right, the entrapped fluid in theright-hand end of valve |8I flowing out to tank 96 as previously hasbeen described in the description relating to the carriage return phaseof the cycle.

When plunger I80 has assumed its rightmost position, cut-out valve 86 ismanually closed to prevent any fluid from entering the right-hand end ofvalve |8| to tend to displace plunger I80 leftwardly. Port I of valve|8| now is connected directly to port 202 thereof; consequently,

when high pressure fluid flows to move plunger 208 of valve 201rightwardly to permit cutter head tripping, etc., it need not wait untilspring I82 of valve I8I has moved plunger: I 80 rightwardly against therestricting action of facingtime period adjustment valve 85, for plungerI80 already is in its rightmost position, valve 85 being, in effect,inoperative when cut-out valve 86 is closed.

Plunger I9 of valve 11 now is pushed back to its former rightmostposition, and the machine is in condition to operate without employing afacing time period in the operating cycl thereof,

plunger I80 is already in its rightmost position and that cut-out valve86 is closed to prevent plunger I80 from being moved leftwardly.

Threading operation and threading cycle variations Phase for phase, theoperation of the machine during threading is the same as that duringturning; consequently, there is no necessity for repeating the detailedoperation of such phases. The following facts, however, should be noted.

First, since all threads require that the movement of the work and therotation of the cutting tool be synchronized in a single definiterelationship during the entire threading cut, it is not possible toemploy more than one rate of axial feed of the carriage during thethreading cut. Secondly, since the coarse axial feed movement of thecarriage is considerably faster than that generally desired to producethreads, the choice of 'axial feed should be restricted to the range offine axial carriage feeds, that is, dog 59 should be removed from T-slot56 and dog 56 should be utilized to actuate plunger 5|.

Lastly, since the serrated cutters employed for threading have a spiralcamming action with the threads that have been formed, it is impossibleto have the carriage dwell for a facing operation,

for this would result in stripping the threads off the work or ruiningthe cutters or both. Consequently, for threading operation, the machinemust be conditioned to eliminate the facing phase of cycle operation.

Thus, threading operation of a machine dispenses with any facing andwith any coarse and subsequently flne axial carriage travel. Further, itgenerally is restricted to flne axial carriage travel. However, thecentering and chucking phase previously described may or may not beemployed, depending on the character of the work. r a

Inthreading, it is possible to operate the machine in a manner which isdifierent from any everything being arranged as before except thatpreviously discussed. Since the serrated cutters eventually can havesufficient contact with the threaded work to draw carriage I6 towardcutter head 20 without having motor 45 serve for this purpose, it ispossible to have the carriage I6 advance under the action of motor 45only until the engagement between the formed threads and the serratedcutters is suflicient to effect further rightward carriage movement.

Figure 4 shows an arrangement of the dogs for eifecting such operationof the machine, there being no work centering phase of cycle operationbecause dog I0 has been removed from T-slot 56 of carriage I6. I

Now, after the operator depresses foot treadle 53 to start the cycle,the carriage is moved rapidly rightward until'dog 58 presses plunger 5|to fine axial feed position, Motor45 serves to move carriage I6rightwardly at the fine axial feed rate until dog 51 presses plunger 5|to stop position. The high pressure fluid then is by-passed, as haspreviously been described, and further carriage movement toward cutterhead is effected by the engagement of the serrated cutters with thework.

Since piston 46 moves rightwardly along with carriage I6, the fluid inthe right-hand end of motor 45 must be displaced to tank 96 manunrestricted manner. Referring to Figure 2 which shows the circuit instop position of the and out port i2| thereof through lines I25, I26,and H4 to port lli of valve 50 and output I29 thereof through lines J30and iii to tank 96.

Continuing rightward movement of carriage l6 causes dog 16 to contactrocker II to effect leftward movement of plunger 19 of valve H. Thesequence of operation then continues as has previously been discussed;however, the time delay feature which effects the facing phase ofoperation is eliminated as has previously been mentioned and described.

Other embodiments Obviously, any type of yoke actuated cutting tool maybe mounted on the spindle of the machine in preference to the onedisclosed, which, as has heretofore been mentioned, is of the samegeneral character as that'disclo'sed by Shearer in United States Patent1,760,560 and which is primarily adapted for the external cutting ofcylindrical surfaces or of conical surfaces whose length does not exceedthat of the cutting faces of the cutters, whose cutting faces may beplain for turning and serrated for threading.

Other types of yoke actuated tools would include one of the characterdisclosed in United States application Serial No. 268,966, filed April.20, 1939, which would serve for essentially the tripping mechanismstherein, such as those disclosed in United States Patents 2,154,006 and2,054,029 and in United States Patent application Serial No. 350,811,filed on even date herewith, may be mounted on the spindle of themachine. The tripping action of the yoke mechanism 26 i would then bedispensed with by disconnecting piston 28 of motor 21 from the yokemechanism,

a suitable linkage being provided to permit piston 28 to press rod 9|rightwardly, member 90 of linkage 30 no longer being suitable for thatpurpose, for yoke mechanism 26 no longer would be actuated to rotateclockwise for cutter tripping movement.

With respect to these later mentioned tools, the one disclosed in UnitedStates Patent 2,154,006 would serve for essentially the same purposes asthe one disclosed by Shearer. That disclosed in United States Patent2,054,029 would serve for generating tapered (threaded or bored)internal surfaces. Also, that disclosed in United States Patentapplication Serial No. 350,811, filed on even date herewith wouldservefor generating tapered, (threaded or bored) external surfaces.

Likewise, it is to be understood that whether the work be clamped fornon-rotary movement and the tool be rotated, or whether the work berotated and the tool be stationary, is merely a matter of choice; forthe carriage may be provided with a work rotating mechanism, and toolspindle i I may be non-rotatably mounted in machine frame i0.

Further, the tool may be non-rotatably mounted on the carriage, and thework may be clamped in a rotatable yoke operated chuck mounted on beclamped in a non-rotatable yoke operated chuck carried by spindle Hwhich may be nonrotatably mounted in machine frame l0.

Since such and further embodiments may be effected, it is apparent thatthe construction of the machine, in this respect, is capable of a largedegree of flexibility.

The machine further is adapted to thread or turn internal or externalsurfaces of straight or tapered configuration and having one or aplurality of progressively enlarged diameters. The tapered surfacesfurther may be generated. Work may be centered or chucked during aperiod of reduced forward movement of the carriage, The cutting can beeffected at one rate or can be effected at some one rate and asubsequently different rate. Work may be faced and tool marks may beremoved therefrom. All of these features are highly desirable andtogether with the other novel features of the machine, cause the machineto be practically universal in its application to threading or turningoperations- Further, the manner of supporting work for centeringrelationship is especially conducive to having the formed surfacesthereof beconcentric therewith. The long length of the spring 4i assureshaving appreciably no undesirable build up of centering pressure ascenter 38 moves rightwardly within sleeve 36 during cutting operation.The adjustment 42 permits of initial ad- Justments of center 38, withrespect to the cutter head 20, to particularly suit certain types andlengths of work.

Still further, the snap action of the rocker 18 and the detent 82assures quick movement of plunger 19 toeffect opening of the cutter headin an instantaneous fashion when the machine is in threading operationposition. Thus, the engagement of the cutters with the work isterminated at the instant that the carriage travel stops, consequently,no injury, due to delayed opening of the cutters, can occur to eitherthe formed threads or the cutting serrations.

While the schematic diagram shown in Figure 2 fullyillustrates themanner in which the vari-.

ous valves, fluid motors, and other mechanisms are co-operativelycombined, it should be understood that certain ofthese parts can bereplaced by a plurality of standard valve structures, fiuid motors,etc., which are combined to have equivalent operating characteristics.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within claims are thereforeintended to be embraced therein.

What is claimedand desired to be secured by United States Letters Patentis:

1. In a cutting machine, a structure mounted for rectilinear movement; afiuid motor connected to said structure and operable to move it from aninitial position to a final position; a valve for reversing the fluidflow in said fluid motor; a fluid operated device for operating saidvalve; means automatically operable substantially when said structureattains said final position, for energizing said fluidoperated deviceand causins said valve and fluid motor to return said structure towardinitial position; and means for automatically actuating said valve toarrest said structure in initial position.

2. The machine defined in claim 1, wherein said last named meanscomprises a member having a lost-motion connection with said structureand adapted to be picked up by the latter slightly before it attainsinitial position. v

3. In a cutting machine, a cutting device and a work holding devicemounted for relative rotation and for relative axial movement; a fluidmotor for moving one of said devices toward the other, so as to bringthe work and said cutting device into cooperative relationship, saidcutting device haying release means for shifting it into non-cuttingposition; control means for automatically actuating said release meanswhen said one device attains a predetermined position, and means,automatically actuated by said last named means for causing said fluidmotor to return said one device to initial position.

4. The machine defined in claim 3, together with means for automaticallyactuating said release means so as to restore said cutting device.

to cutting condition when said one device attains initial position. I

5. The machine defined in claim 3, wherein said control means comprisesa quick-action valve, and a fluid motor connected to said release means,so that the latter will shift the cutting device into non-cuttingposition as soon as said one device attains said predeterminedposition.- 6. The machine defined in claim 3, wherein said. controlmeans comprises a valve connecting a fluid operated device to a sourceof fluid energy, said fluid operated device being connected to saidrelease means; and means for restricting the flow of fluid into saidfluid operated device for delaying the release action of said cuttingdevice until after said one device comes to rest.

7. A cutting machine comprising a rotary cutter and an axially movablecarriage; a hydraulic motor connected to said carriage for moving saidcarriage in either direction said motor having a fluid inlet and a fluidoutlet; a main control valve having a plurality of operative Dsitions; ahydraulic system including connections between said valve and saidmotor; means supplying fluid under pressure to said system; a tank insaid system for receiving discharged fluid; said system including aplurality of connections between the outlet of said hydraulic motor andsaid tank; adjustable valves restricting the flow through said lastnamed connections; said main control valve being adapted in accordanceto its position, to selectively direct the-flow to one of saidconnections, and means actuated b the carriage in its movement toselectively position said main control valve.

8. A cutting machine comprising a rotary cutter and an axially movablecarriage, a hydraulic motor for said carriage, said motor having a fluidinlet and a fluid outlet; a main control valve adapted to be actuated bythe movement of said carriage for directing fluid to said inlet andregulating therate of discharge from said outlet; means for reversingthe fluid supply to said motor in response to the movement of saidcarriage and for positioning said control valve to stop the supply offluid to said fluid inlet.

9. A combined turning and threading machine comprising a cuttingelement; a rotary head carrying said element; a movable center withinsaid head; a movable work holding carriage in axial alignment with saidhead; and elongated spring for holding said center in engagement withwork held by said carriage as said carriage moves toward said cuttingelement.

10. A combined turning and threadingmachine comprising a rotary cuttingelement; a head carrying said element; an axially movable carriage inaligmnent with said element; a centering means on said carriage;imparting a relatively slow movement of said carriage toward saidelement to provide a work engaging and centering period, said means alsoproviding a subsequent relatively rapid move ment 'of said carriagetoward saidcutting'ele- "ment prior to engagement of said cuttingeleformed, and a final ment with the work and a spring pressed centeraxially movable within said *head for engaging the work as it moveswith'said'carriage.

11. In a cutting machine, a cutting devic'e'and a work holding devicemounted for relativerotation and for relative axial movement; a fluidmotor connected to one of said devices and adapted to move it atcontrolled speeds toward the otherdevice and bringing the work andcutting device into cutting relationship; quick-action means,automatically actuatedwhen said one device attainsa predeterminedposition, for causing said cutting device to be released from the workand for causing said fluidmotor to restore said one device to initialposition, said quick-action means comprising a valve having a plungerwhich is rapidly displaced in actuated position by mutual quick-actingcamming between a rocker member engaged by said plunger and a springpressed detent mounted in said machine.

12. The machine defined in claim 1 wherein said last named meanscomprises a member carried by said structure.

13. The machine defined in claim 3, wherein said control means comprisesa valve connecting a fluid operated device to a source of fluid energy,said fluid operated device being connected to said release means, andadjustable means for restricting the flow of fluid into said fluidoperating device for delaying the release action of said cutting deviceuntil a predetermined period after said one device comes to rest.

14. A cutting machine comprising a rotary cutting tool and an axiallymovable carriage, a motor for imparting axial movement to said carriage,manual means for starting said motor, control means for said motormounted to be actuated in response to movement 01 said carriage; meansfor driving said motor, in response to said control means, to provide arelatively slow movement or said carriage during a work chucking and/orcentering period, a rapid movement .of said carriage 'to cuttingposition, a plurality of relative axial movements of diflerent' speedsduring a cutting phase, a period during which axial movement is stoppedand a work facing operation is perreturn movement or said carriage; andmeans automatically operated by the carriage for withdrawing the toolbefore the return movement of the carriage.

15. A cutting machine comprising arotary cutting tool and an axiallymovable carriage; a motor for imparting an axial movement of saidcarriage to and from said tool; a control element for positioning saidtool in cutting position; and means responsive to said carriage movementfor withdrawing said tool, with a snap action at the end 01' saidmovement of the carriage toward said tool.

16. A cutting machine as described in claim 14 wherein an adjustablemeans is provided to remeans for automatically tard the withdrawing ofsaid tool whereby it forms an annular face on said work.

17. In a cutting machine, a work holding device comprising a pair 01'work supports disposed in spaced axial alignment and adapted to have aworkpiece positioned therebetween; a carriage mounting one support foraxial movement toward and away from the other support; and the latterbeing yleldingly movable in unison with said one support when aworkpiece is positioned therebetween; a cutting device cooperating withsaid supports and operable to coact in cutting relationship with aworkpiece carried thereby when the workpiece is moved into apredetermined axial position with respect to said cutting device; a lopower operated mechanism connected to one of said supports and operableto move it toward the other support; and control means, automaticallyoperable in accordance withmovement of said one support, for causingsaid mechanism to move said one support toward the other at acomparatively fast speed, until the spacing between said supports hasbeen decreased to a distance slightly greater than the length 01' theworkpiece to be operated upon, and to then automatically move said onesupport at a slower speed to permit a workpiece to be positioned betweensaid supports, and to then move both of said supports and said workpiecein unison at a last speed. to bring the workpiece rapidly into cuttingrelationship with said cutting device.

device and bring the work and cutting device into cutting relationship;and quick-action means, automatically actuated when said one deviceattains a predetermined position, for causing said cutting device to 'bereleased from the work and for causing said fluid motor to restore saidone device to initial position, said cutting device embodying a yokeactuated release, and said quick-action means comprising a second fluidmotor operablyconnected to said yoke.

SAMUEL W. MATHIAS.

